ARM: atmel: spl: add weak bus matrix init function
[platform/kernel/u-boot.git] / arch / arm / cpu / at91-common / spl_atmel.c
1 /*
2  * Copyright (C) 2013 Atmel Corporation
3  *                    Bo Shen <voice.shen@atmel.com>
4  *
5  * SPDX-License-Identifier:     GPL-2.0+
6  */
7
8 #include <common.h>
9 #include <asm/io.h>
10 #include <asm/arch/at91_common.h>
11 #include <asm/arch/at91_pit.h>
12 #include <asm/arch/at91_pmc.h>
13 #include <asm/arch/at91_rstc.h>
14 #include <asm/arch/at91_wdt.h>
15 #include <asm/arch/clk.h>
16 #include <spl.h>
17
18 DECLARE_GLOBAL_DATA_PTR;
19
20 static void switch_to_main_crystal_osc(void)
21 {
22         struct at91_pmc *pmc = (struct at91_pmc *)ATMEL_BASE_PMC;
23         u32 tmp;
24
25         tmp = readl(&pmc->mor);
26         tmp &= ~AT91_PMC_MOR_OSCOUNT(0xff);
27         tmp &= ~AT91_PMC_MOR_KEY(0xff);
28         tmp |= AT91_PMC_MOR_MOSCEN;
29         tmp |= AT91_PMC_MOR_OSCOUNT(8);
30         tmp |= AT91_PMC_MOR_KEY(0x37);
31         writel(tmp, &pmc->mor);
32         while (!(readl(&pmc->sr) & AT91_PMC_IXR_MOSCS))
33                 ;
34
35         tmp = readl(&pmc->mor);
36         tmp &= ~AT91_PMC_MOR_OSCBYPASS;
37         tmp &= ~AT91_PMC_MOR_KEY(0xff);
38         tmp |= AT91_PMC_MOR_KEY(0x37);
39         writel(tmp, &pmc->mor);
40
41         tmp = readl(&pmc->mor);
42         tmp |= AT91_PMC_MOR_MOSCSEL;
43         tmp &= ~AT91_PMC_MOR_KEY(0xff);
44         tmp |= AT91_PMC_MOR_KEY(0x37);
45         writel(tmp, &pmc->mor);
46
47         while (!(readl(&pmc->sr) & AT91_PMC_IXR_MOSCSELS))
48                 ;
49
50         /* Wait until MAINRDY field is set to make sure main clock is stable */
51         while (!(readl(&pmc->mcfr) & AT91_PMC_MAINRDY))
52                 ;
53
54         tmp = readl(&pmc->mor);
55         tmp &= ~AT91_PMC_MOR_MOSCRCEN;
56         tmp &= ~AT91_PMC_MOR_KEY(0xff);
57         tmp |= AT91_PMC_MOR_KEY(0x37);
58         writel(tmp, &pmc->mor);
59 }
60
61 __weak void matrix_init(void)
62 {
63         /* This only be used for sama5d4 soc now */
64 }
65
66 void s_init(void)
67 {
68         switch_to_main_crystal_osc();
69
70         /* disable watchdog */
71         at91_disable_wdt();
72
73         /* PMC configuration */
74         at91_pmc_init();
75
76         at91_clock_init(CONFIG_SYS_AT91_MAIN_CLOCK);
77
78         matrix_init();
79
80         timer_init();
81
82         board_early_init_f();
83
84         preloader_console_init();
85
86         mem_init();
87 }